TMS370CX1X Datasheet, PDF (43/50 Pages) Texas Instruments – 8-BIT MICROCONTROLLER

TMS370Cx1x
8-BIT MICROCONTROLLER
SPNS012F – MAY 1987 – REVISED FEBRUARY 1997
SPI master mode external timing characteristics and requirements (see Note 12 and Figure 23)
NO.
38 tc(SPC)M
Cycle time, SPICLK
39 tw(SPCL)M
Pulse duration, SPICLK low
40 tw(SPCH)M
Pulse duration, SPICLK high
41 td(SPCL-SIMOV)M Delay time, SPISIMO valid after SPICLK low (polarity = 1)
42 tv(SPCH-SIMO)M Valid time, SPISIMO data valid after SPICLK high (polarity =1)
43 tsu(SOMI-SPCH)M Setup time, SPISOMI to SPICLK high (polarity = 1)
Valid time, SPISOMI data valid after SPICLK high
44 tv(SPCH-SOMI)M _{(polarity = 1)}
NOTE 12: tc = system-clock cycle time = 1 / SYSCLK
38
MIN
2tc
tc – 45
tc – 55
– 65
tw(SPCH) – 50
0.25 tc + 150
0
MAX
256tc
0.5tc(SPC)+45
0.5tc(SPC)+45
50
UNIT
ns
ns
ns
ns
ns
ns
ns
SPICLK
40
39
41
42
SPISIMO
Data Valid
SPISOMI
43
44
Data Valid
NOTE A: The diagram is for polarity = 1. SPICLK is inverted when polarity = 0.
Figure 23. SPI Master External Timing
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